The invention relates to a method for the diagnosis of non-alcoholic steatohepatitis (NASH), for determining the activity, the stage, or the severity of NASH or for classifying a subject as a potential receiver or non receiver of a treatment of NASH, using miRNA. It also relates to a kit for implementing the method of the invention, and the compounds for use in a method for the treatment of NASH, wherein the subject to be treated is identified, evaluated or classified according to the method of the invention.